How to integrate Kubernetes with Gitlab

Question

I\'m trying to integrate Kubernetes cluster with Gitlab for using the Gitlab Review Apps feature.

• Kubernetes cluster is created via Rancher 1.6
• Runnin

Answer 1

I'm also dying out with kubernetes and GitLab. I've created a couple single-node "clusters" for testing, one with minikube and another via kubeadm.

I answered this question on the GitLab forum but I'm posting my solution below:

API URL

According to the official documentation, the API URL is only https://hostname:port without trailing slash

List secrets

First, I listed the secrets as usual:

$ kubectl get secrets
NAME                           TYPE                                  DATA      AGE
default-token-tpvsd            kubernetes.io/service-account-token   3         2d
k8s-dashboard-sa-token-XXXXX   kubernetes.io/service-account-token   3         1d

Get the service token

$ kubectl -o json get secret k8s-dashboard-sa-token-XXXXX | jq -r '.data.token' | base64 -d
eyJhbGci    ... sjcuNA8w

Get the CA certificate

Then I got the CA certificate directly from the JSON output via jq with a custom selector:

$ kubectl -o json get secret k8s-dashboard-sa-token-XXXXX | jq -r '.data."ca.crt"' | base64 -d - | tee ca.crt
-----BEGIN CERTIFICATE-----
MIICyDCCAbCgAwIBAgIBADANBgkqhkiG9w0BAQsFADAVMRMwEQYDVQQDEwprdWJl
...        ...        ...        ...        ...        ...      
FT55iMtPtFqAOnoYBCiLH6oT6Z1ACxduxPZA/EeQmTUoRJG8joczI0V1cnY=
-----END CERTIFICATE-----

Verity the CA certificate

With the CA certificate on hand you can verify as usual:

$ openssl x509 -in ca.crt -noout -subject -issuer
subject= /CN=kubernetes
issuer= /CN=kubernetes

$ openssl s_client -showcerts -connect 192.168.100.20:6443 < /dev/null &> apiserver.crt

$ openssl verify -verbose -CAfile ca.crt apiserver.crt
apiserver.crt: OK